All these have the same humble origin: a portfolio was (and still is) a case or folder for holding papers, drawings and so on. The word comes from the Italian portafoglio, derived from the verb portare, to carry, and the noun foglio, a sheet of paper. In English, it is first recorded, as 'porto folio', in 1713. Before that, we used the French, portefeuille. That term decribed a case designed to hold official documents of the French government, and then by extension the responsibilities of a cabinet minister. 'Portfolio' took on these meanings, and by the mid 19th century it meant a range of investments. A 'portfolio career' is one made up of short-term, part-time contracts rather than an old-fashioned 'job for life'. The term is most associated with the management thinker Charles Handy, who first used it in 1984. These days, however, a job for life has never seemed more attractive.
'The only limit to our realisation of tomorrow will be our doubts of today' - Franklin D Roosevelt said it
'Moderation is a fatal thing. Nothing succeeds like excess' - oscar wilde said it.